摘要
双钢板-混凝土组合墙(steel-concrete composite wall,SC wall)常用于核电站、超高层等重要结构的承重构件,其在偶然荷载作用下的力学性能也是其推广应用的关键指标。为此,针对火灾下SC墙的抗冲击性能进行研究并给出相关设计建议。首先建立了SC墙在火灾与冲击耦合作用下的有限元模型,在验证模型可靠性基础上,开展了火灾下SC墙抗冲击机理的分析;然后研究了轴力、受火时间、材料强度、冲击能量与抗剪连接件形式等参数对SC墙在火灾下抗冲击性能的影响规律;最后给出了该类构件在耦合工况下跨中峰值挠度的预测公式。结果表明:随着受火时间的增加,SC墙受冲击变形模式由局部冲切逐渐转变为整体弯曲破坏;火灾下,混凝土为SC墙受冲击的主要耗能部件;混凝土强度、轴力与抗剪连接件形式对SC墙在高温下的抗冲击性能影响显著,钢板强度的影响则较小;建议的公式可较合理地预测火灾下SC墙受冲击后的跨中峰值挠度。
Steel-concrete composite wall(SC wall)has been widely employed as the main structural components in nuclear power plants and high-rise buildings.Its performance under accidental loads is a key index for its utilization.In this paper,the mechanical behaviors of SC walls under coupled fire and impact loads are investigated and corresponding design recommendations are given.Firstly,a finite element(FE)model of SC walls under combined fire and impact loads is developed.After validating the FE model,the response mechanism of SC walls under combined fire and impact loads is analyzed.Afterwards,effects of axial force,fire duration,material strength,impact energy and type of shear connectors on the impact resistance performance of components under fire condition are studied.Finally,simplified formula for predicting the maximum mid-span deflection under coupled fire and impact loadings is proposed.In view of the failure pattern,the outer steel plate on the surface exposed to fire presents wavy buckling.With the increase of fire duration,the deformation mode of SC walls changes from local punching deformation to overall flexural deformation.Under combined fire and impact loads,concrete is observed to be the main energy consumption component within the SC walls.The peak membrane force and the maximum mid-span deflection are employed to analyze the impact resistance of the SC walls.Test results show that the fire duration has a significant effect on the impact resistance.The peak membrane force of the SC walls reduces by approximately 36%under 90 min fire duration,while the maximum mid-span deflection increases by 50%.The concrete strength,axial force and type of shear connectors also obviously affect the impact resistance of the SC walls,while the influence of the yield strength of steel plate is moderate.The proposed formula can reasonably predict the maximum deflection of the SC walls under combined fire and impact loads.
作者
杨耀堂
王蕊
赵晖
侯川川
YANG Yaotang;WANG Rui;ZHAO Hui;HOU Chuanchuan(College of Civil Engineering,Taiyuan University of Technology,Taiyuan 030024,Shanxi,China;School of Transportation Science and Engineering,Beihang University,Beijing 100191,China)
出处
《爆炸与冲击》
EI
CAS
CSCD
北大核心
2024年第1期11-25,共15页
Explosion and Shock Waves
基金
国家自然科学基金(52108162)
山西省留学回国人员科技活动择优资助项目(20210010)。
